Multifunctional Adhesive Hydrogel for Rapid Cardiac Hemostasis and Antibacterial Protection

ABSTRACT Severe cardiac bleeding requires rapid and stable sealing in highly dynamic and continuously wet environments, where most existing hemostatic agents fail to provide sufficient performance. In this work, we introduce a multifunctional polyacrylamide/gelatin/tannic acid hydrogel (PGT) engineered to deliver strong wet adhesion, rapid coagulation, robust mechanical stability, and antibacterial activity simultaneously. The tannic acid(TA) coating strengthens the polymer network by promoting multivalent hydrogen bonding and metal–phenolic coordination, thereby improving both mechanical integrity and interfacial adhesion to moist biological tissues. Among the hydrogel formulations, the PGT10, coated with 10% TA solution, exhibited exceptional performance, achieving instantaneous sealing of a porcine cardiac defect without initial leakage and maintaining stable adhesion under continuous pressure and physiological movement. PGT10 also demonstrated superior hemostatic efficacy in in vivo liver puncture models and porcine whole‐blood assays, markedly reducing blood loss and accelerating clot formation. Additionally, the PGT exhibited excellent cytocompatibility, low hemolysis, and strong antibacterial effects against E. coli and S. aureus . Collectively, these findings highlight the promise of the PGTs as rapidly deployable, biocompatible bioadhesive patches capable of enabling effective bleeding control in high‐motion organs such as the heart and liver. These advantages collectively support its clinical translation potential in critical emergency care settings.